Chairs that are used for a variety of purposes, such as office chairs, chairs for home use, vehicle chairs or seats etc. sometimes include a special lumbar support device to support the lower back of the user. Usually this device is a softly rounded protrusion or cushion that is disposed on the front of the back support and a certain level above the seat. Below this protrusion, the sitting user may push in his pelvis so that the protrusion bears against the lower back so that the lower back is in an ergonomically desirable, sway-backed or bow shaped position.
A chair that has a support panel that is divided in a front and back part is already known in U.S. Pat. No. 1,836,630. However, that chair has a back support that is non-rotatably attached to the rear part of the support panel. The rear part is non-rotatably attached to the frame of the chair. The fact that the rear part of the support panel and the back support are non-rotatably attached to one another has the consequence that the user risks to slide forwardly along the seat so that the bottom loses is supporting contact with the back support in the area that is below the lumbar support device. In this way, the ergonomically desirable sway-back position of the spine is mediocre. In other words, the body posture of the user becomes wrong and tiresome which can easily create back pain.
A chair of the type described in ingress is also known in U.S. Pat. No. 4,709,961. That chair includes a cushion that is included in the seat and a rear seating area that when the chair is used may be recessed relative to the front seating area. More particularly, by turning the front seating panel upwardly and adjusting its rearward/downward position with an adjustment mechanism against a rear support panel that is sloping. Even in this case, the rear part of the support panel is non-rotatably or unmovably attached to the frame and non-rotatably attached to the back support. This means that the risk for sliding forward along the seat is apparent.
The present invention has the object of solving the above-mentioned problems associated with the earlier known chairs as mentioned above and to create an improved chair. A fundamental object of the invention is thus to create a chair that ensures a lasting and satisfactory support contact between the bottom of the user and the lower part of the back support. Another object is to create a chair that provides a complete support of the user's back against the lumbar support of the back support without requiring that the user must intentionally push in the bottom against the lower part of the back support that is situated below the lumbar support device.
The chair of the present invention is comfortable and easy to adjust to the specific needs of the user. The chair also provides good support for the back of the user. The user of the chair may also move within the chair without losing the good support of the back of the user.